Higher speed digital communication links operating at 40 Gbps and 100 Gbps employ transceivers that transmit 10 Gbps serial data over 4 or 10 parallel lanes to achieve the 40 Gbps or 100 Gbps aggregate data rates, respectively. Modular transceivers and direct attached pluggable module assemblies that support 40 Gbps transmission are currently packaged in Quad Small Formfactor Pluggable (QSFP+) modules as specified in MSA (Multiple Source Agreement) document INF-8438 and Industry Ad hoc group document SFF-8436.
These types of modules must have a means to self-lock when inserted into a host enclosure module cage and must also allow insertion and extraction without the use of special tools. Hence, the QSFP+ modules and direct attached pluggable cable assemblies employ a latching mechanism that facilitates convenient module insertion and removal. Currently, the standard actuation method for removing the module from the host cage assembly is to use a bail type actuator as illustrated in U.S. Pat. No. 7,445,485 (see FIG. 1, showing a prior art module 20). Pulling the bail tab 21 causes a metal spring finger to slide outward disengaging the latching mechanism. Examples of two other prior art modules 22, 23 with typical pull tabs 21 and a prior art module 24 with a transceiver release bail 25 are shown in FIG. 2. Although the actuation method for these direct attached pluggable module assemblies is effective, a mechanism with fewer components and improved ergonomic design is desirable.
In addition, direct attached pluggable modules have no standard method for managing cable retention. For example, as shown in FIG. 3, in one direct attach optical module 30, cable retention is achieved by clamping the aramid yarn 31 of the cable 35 to the module housing 37 using a screw 32 and washer 33. Once attached, the cable 35 is placed in a cylindrical channel 34 which extends beyond the housing wall forming a cable inlet in order to provide a means for attaching a rubber boot for bend radius control.
FIG. 4, shows an exploded view of a typical MPO connector 40. The MPO connector 40 has a boot 41, crimp sleeve 42, core housing 43, spring 44, alignment pins 45, ferrule 47, and MPO housing 46. MPO connectors such as the one shown in FIG. 4, are able to implement bend radius control, cable retention, and an ergonomic actuation in a single assembly which until now, has not been implemented for direct attached pluggable modules. As a result, it is desirable to modify the design of a direct attached pluggable module in order to take advantage of the desirable elements of an MPO-style connector.